In order to reduce the damage of smoking to a smoker and public health, a cigarette harm reduction technique has become a main means to reduce the inhalation of a harmful substance in a cigarette smoke. The cigarette harm reduction technique in the prior art mainly includes the change in the combustion state of a cigarette and the adoption in a special filter tip to reduce the harmful components of a mainstream smoke. The former uses a high permeability cigarette paper or blends a tobacco flake, an expanded tobacco shred and a stem in a tobacco shred, wherein the high permeability cigarette paper may dilute the smoke of a cigarette part and improve a burning speed; blending the tobacco flake, the expanded shred and the stem may increase the filling of the tobacco shred and speed up the burning speed of the cigarette, but reduce the number of the smoking at the same time, this will result in an increase in the absolute amount of smoked cigarettes. The latter uses a filter tip trapping technique and a filter tip ventilation dilution technique, the filter tip trapping technique is to add an activated carbon, a zeolite and other adsorbents in the filter tip or make binary or multiple composite filter tips and the special-shaped filter tips in different structures, this may selectively trap the harmful components in the mainstream smoke, but have the problems such as some aroma components trapped by a filter material, affecting the taste of the cigarette, a complex production process and so on; the filter tip ventilation dilution technique is to perforate a tipping paper, use a high permeability forming paper or make a groove in a filter rod, etc., so that air is introduced into the filter tip to dilute the mainstream smoke when smoking the cigarette, so as to achieve the purpose of harm reduction, however, due to the dilution of the smoke, it is needed to maintain the taste of the cigarette by adding an essence and a flavor and using compensation measures.
The comfort of the cigarette has a greater relationship with the moisture of the smoke, the study found that the suitability of the smoke moisture would make the smoke be soft and delicate, small irritation, and better sensory comfort; when the smoke moisture content is low, this will lead to dry smoke, bigger irritation and reduced sensory comfort. The nicotine in the cigarette smoke comprises the nicotine under a combination state and the nicotine under a free state, the smoke irritation is mainly determined by the content of the nicotine under the free state. The relative content of the two states of the nicotine is related to the environment (for example, humidity, and PH) of the smoke. The nicotine under the free state may be combined with hydrogen ions in the smoke to form a salt (the nicotine under the combination state), when the moisture content (humidity) of the smoke is low, the hydrogen ion concentration decreases, this will inhibit the formation of the nicotine under the combination state while also decreasing the water solubility of the nicotine under the combination state, this makes it easier to decompose the nicotine under the combination state into the nicotine under the free state, so that the relative content of the nicotine under the free state increases, and the nicotine under the free state/the total nicotine also increases, resulting in the increase in the irritation and dryness. However, if the humidity of the smoke is too large, the nicotine under the free state will be too low, which will fail to reach the physiological strength required by the smoker. Therefore, the change of the moisture content (humidity) of the smoke will significantly affect the state distribution of the nicotine, so that the nicotine under the free state and the ratio of the nicotine under the free state/the nicotine will change significantly. Under low humidity conditions, the content of the nicotine under the free state and the ratio of the nicotine under the free state to the nicotine both increase, so that the cigarette product is easier to produce irritation when being smoked in an dry environment than being smoked in an wet environment. In order to make the product have the higher ratio of the nicotine under the free state to the nicotine, and ensure the stability of the nicotine under different wet environments to solve the problem of the bigger irritation of the product in the dry environment, a glycerol may be added into the tobacco shred to increase the moisture of the cigarette smoke and improve the sensor comfort of the cigarette. However, the study has shown that the glycerol and other humectants in the cigarette shred may have thermal cracking under the burning temperature (900° C.) of the cigarette to produce harmful aldehydes (especially acrolein).
When the cigarette with a middle or low tar is smoked, although the tar content is lowered, this also has lowered physiological satisfaction, decreased aroma amount, worse comfort and other problems at the same time. Currently, the problems of dilution and faint smokes due to the lowered tar amount of the cigarette are solved by means of adding the essence and the flavor, to improve the odor of the cigarette, enrich the aroma amount and maintain a good sensory quality. A compensation method in the prior art for adding the essence and the flavor is to add a cotton thread impregnated with liquid flavor essence or to add a flavor microcapsule to the filter tip during the course of the acetate fiber molding of the filter tip so that fragrance is released during the smoking to improve the smoking taste of the cigarette. In the process of the smoking, as the essence and the flavor are increasingly reduced due to the continuous release, the mixture of each smoke and the essence components is inconsistent, so that the smoking taste of each puff is quite different. In addition, the microcapsule containing the flavor may release the aroma components only when being broken, which brings inconvenience to the smoking.